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MIPS as indicator for performance

Question asked by melamud.michael on Jul 15, 2013
Latest reply on Jul 18, 2013 by
Hi ,

I am working on Cortex M4F CPU , its 168 MHZ , i know that Cortex M4F is 1.25 MIPS per MHZ so a quick calculation will give me total of 210 MIPS .

Lets say i have an algorithm  that runs 3 seconds , so what should i say for example to the costumer , if you want a 3 second performance you need to give me a CPU that is able to give me 210 MIPS ?  suppose its true , i have few follow up questions :

1.  Performance is also effected by various factors ,for example : using the FPU , the DSP capabilities of the CPU , the speed of the SDIO interface , the file system implementation , and event the SD-card class , so given this factors , the 210 MIPS is a really a rough estimation , correct?
2. Who also can say that in the whole 3 seconds of my run-time i am using all of the 210 available MIPS  , maybe i am using in average only 60% 70%  of my CPU  ?  will measuring the average CPU consumption give me a better estimate on how much MIPS that i am using?
     (Suppose i am using only 50% of the CPU average,so with that i need only 105 MIPS and not 210 MIPS , correct?)